Calendar sync with Windows Phone 7

Calendar sync with Windows Phone 7

Hi.
A newbie to ZOHO and pretty pleased so far.  Only niggle is when I make a new appointment on my phone it doesn't seem to sync with my ZOHO calendar.  If I make an appointment on my ZOHO calendar then it appears on my phone calendar pretty quickly after I sync.
Any ideas?  I have just downloaded the latest version(7.8) on my mobile.
Cheers